I don't know how to keep this topic away from http://lesswrong.com/lw/gw/politics_is_the_mindkiller/ , so I'm just going to exhort everyone to try to keep this about rationality and not about politics as usual. I myself have strong opinions here, which I'm deliberately squelching.
So I got to thinking about the issue of gun control in the wake of a recent school shooting in the US, specifically from the POV of minimizing presumed-innocents getting randomly shot. Please limit discussion to that *specific* issue, or we'll be here all year.
My question is not so much "Is strict gun control or lots of guns better for us [in the sole context of minimizing presumed-innocents getting randomly shot]?", although I'm certainly interested in knowing the answer to that, but I think if that was answerable we as a culture wouldn't still be arguing about it.
Let's try a different question, though: how would we know?
That is, what non-magical statistical evidence could someone give that would actually settle the question reasonably well (let's say, at about the same level as "smoking causes cancer", or so)?
As a first pass I looked at http://en.wikipedia.org/wiki/List_of_countries_by_intentional_homicide_rate and http://en.wikipedia.org/wiki/List_of_countries_by_firearm-related_death_rate and I noted that the US, which is famously kind of all about the guns, has significantly higher rates than other first-world countries. I had gone into this with a deliberate desire to win, in the less wrong sense, so I accepted that this strongly speaks against my personal beliefs (my default stance is that all teachers should have concealed carry permits and mandatory shooting range time requirements), and was about to update (well, utterly obliterate) those beliefs, when I went "Now, hold on. In the context of first world countries, the US has relatively lax gun control, and we seem to rather enjoy killing each other. How do I know those are causally related, though? Is it not just as likely that, for example, we have all the homicidally crazy people, and that that leads to both of those things? It doesn't seem to be the case that, say, in the UK, you have large-scale secret hoarding of guns; if that was the case, they'd be closer to use in gun-related homicides, I would think. But just because it didn't happen in the UK doesn't mean it wouldn't happen here."
At that point I realized that I don't know, even in theory, how to tell what the answer to my question is, or what evidence would be strong evidence for one position or the other. I am not strong enough as a rationalist or a statistician.
So, I thought I'd ask LW, which is full of people better at those things than I am. :)
Have at.
-Robin
There are two obvious effects (guns are more deadly than other weapons, but guns are also a deterrent) and it is not clear which is stronger. It's one of those issues where natural experiments or instrumental variables are our best bet for gaining knowledge, and of course anyone with a stat background will know the troubles with those techniques.
That said, there are studies using those techniques and they are better than a cursory glance at gun laws and homicide rates by country (or by state). And, to my understanding, the results of those studies are resoundly mixed. Some of these are quite controversial, but we're talking about tricky statistical techniques surrounding an emotional political issue, so controversy will abound even if the results are sound.
My takeaway is that this is not an issue worth getting very passionate about one way or the other. Your knowledge should drive your emotions, and if you don't know what effect is strongest, then you should save your emotional energy for more clear-cut or important causes.
If anyone knows of any very elegant studies, please correct me. Obviously I haven't read the whole literature.
Oh, I like this. I like this a lot. The underlying attitude, I mean. I'm going see if I can't extrapolate a general policy from this, actually. Something like:
"In a world where there still exist children that live (or, more likely, die) on garbage heaps, the fact that we're still arguing about [whatever issue] implies to me that it's not a low hanging fruit, and we should just go work on those instead."